Rapid development and evaluation of fast process based models in Mobius

The open source Mobius framework allows for quick develoment of models based on ODE- and discrete-timestep equations. One can build and explore many model structures with only small modifications to the model code. Model run speed is fast, making it feasible to do extensive automated parameter space exploration, for instance using optimizers or MCMC algorithms. The framework can compile models to a format where they are accessible for interaction using the Python scripting language. Moreover, several calibration and uncertainty analysis tools in Python are already set up so that they can be used with any Mobius model. This can then be used to evaluate model structures using Bayesian methods. We show an example of evaluating a few DOC catchment models using this framework. Modelling frameworks are a good alternative to one-size-fits-all models, and we hope Mobius will be a useful tool for promoting more robust modelling.